Chionomus quadrispinosus ( Muir & Giffard, 1924 ) Weglarz & Bartlett, 2020

Weglarz, Kathryn M. & Bartlett, Charles R, 2020, A revision of the planthopper genus Chionomus Fennah (Hemiptera: Fulgoroidea: Delphacidae), Zootaxa 4811 (1), pp. 1-63 : 34-35

Chionomus quadrispinosus ( Muir & Giffard, 1924) , new combination

( Figures 15 , 18i & l , 30 )

Delphacodes quadrispinosa Muir & Giffard, 1924: 37 .

Type Locality. Nicaragua, San Marcos .

Diagnosis. Body dark brown to brown, with white markings. Vertex quadrate; foveae of frons and vertex concolorous with body. Carinae distinct, off-white in color; antennae light brown. Pronotum concolorous with mesonotum, paranota white along margins. Armature of diaphragm U-shaped; inner and outer angles of parameres diverging, basal angle produced, rounded. Aedeagus tubular, with two rows of teeth along venter, curved dorsad; base enlarged, quadrate. Segment X armed with 4 distinct processes, first processes closely approximated, second processes nearly touching.

Description. Color. Macropter. Body dark, brunneous, shining, with white or ivory markings. Carinae of head (excluding genal carinae) distinct, off-white to ivory in color; median carinae of vertex concolorous with foveae. Antennae light brown, paler at apex. Pronotum concolorous with mesonotum, paranota white to ivory along margins. Mesonotum dark, median and lateral carinae obscure. Legs cream colored to yellow, apex of tarsi brown. Forewings hyaline, distinct dark spot just before apex of clavus. Abdomen dark brown, thin white line along caudal edge of each segment, lateral projections of sternites white. Pygofer and segment X brown. Brachypter. Similar to above. Tegmina dark, infuscate, white stripe along apex, darkened spot near apex of clavus. Structure. Body. Length (in mm) macropter 1.60±0.02 (n=2); ♂ brachypter 1.46±0.12 (n=5); ♀ brachypter 1.69 ±0.09 (n=4); width ♂ 0.62±0.07 (n=16); ♀ 0.64±0.04 (n=4). Head. Vertex length 0.14±0.03 (n=16); vertex width 0.16±0.02 (n=13); frons length 0.41±0.06 (n=16); frons width 0.19±0.03 (n=16). Macropter. Carinae of vertex distinct, stem of Y-shaped obscure. In lateral view ( Figure 15b ), fastigium rounded; projecting in front of the eye about half the length of eye. Carinae of frons and clypeus distinct ( Figure 15c ), frons subparallel, widest just below ventral edge of compound eyes. Antennal segments subequal in length, segment II wider than segment I; 2nd segment sparsely setaceous, bearing sensory pits arranged 3, 3, 2, 2, evenly spaced around segment. Sensory pits surrounded by small black setae. Brachypter. Same as above.

Thorax. Macropter. Carinae of mesonotum weak, median carina ending anterior to scutellum, lateral carinae faint, diverging posteriorly, reaching hind margin. Forelegs with 2 rows setae on ventral margin of femora; legs mostly bare. Calcar bearing 18–22 small teeth. Brachypter. Same as above but with lateral carinae mesonotum evident; tegmina apically rounded, reaching the midsection of the pygofer.

Abdomen. Macropter. Compressed dorsoventrally, tapering caudad to truncate apex; abdominal spiracles surrounded with one or two long, fine setae.

Genitalia. Pygofer in lateral view ( Figure 15d ) about as long dorsally as ventrad, ventral margin sinuate. In caudal view ( Figure 15e , 30a ), 5/6ths as tall as wide, rounded; margins raised, dorsolateral margins produced, carinate. Opening to inner chamber trapezoidal, pointed ventrad. Armature of diaphragm U-shaped, fitting aedeagus, smooth, distinctly projecting caudad. Parameres, widest in basal third, basal angle projecting, rounded; dorsolaterally diverging, apices concave, lateral margins concave, inner produced, quadrate, outer angles produced, rounded. Aedeagus oval in cross-section, curved ventrad, consistent in width excluding base, two rows of evenly spaced teeth along ventral margin; base wide, quadrate. Gonopore ventral, subapical. Segment X quadrate, wider than tall; with 4 processes, first pair distinct, closely approximated, second pair longer than first, more closely approximated, nearly touching. Segment XI produced, about 1/3rd length of segment X.

Plant associations. Phaseolus vulgaris L. (kidney bean, Fabaceae ); Galactia elliottii Nutt. (Elliot’s milkpea, Fabaceae ) (Label information).

Distribution. USA: FL, LA; Dominican Republic; Guatemala; Honduras; Nicaragua; Costa Rica. Also reported Cuba ( Muir & Giffard 1924).

GenBank accession number. Molecular sequence was unable to be generated at the time of this study.

Remarks. Chionomus quadrispinosus is closely allied with C. dissipatus and C. gluciophilus and has an overlapping distribution (see Remarks of C. dissipatus ). Chionomus quadrispinosus tends to be darker and can be distinguished by the armature of the diaphragm and shape of the aedeagus. This species is most frequently collected in brachypterous form.

The primary type material of this species appears to be lost. According to Muir and Giffard (1924: 37), the types of this species “...were standing under the name of culta Van Duzee in the Pomona [College] and Crawford collections.” The Pomona College (Claremont, CA) collection was reportedly transferred to the California Academy of Science; however, the Crawford types are not listed in the California Academy of Science’s type specimen database, and a trip to the collection failed to find it. BPBM was also checked because many of Muir’s type specimens are housed there .

Type material examined. Holotype [Pomona Collection, transferred to CASC]: missing.

Figures

FIGURE 15. Habitus of Chionomus quadrispinosus. A. dorsal habitus; B. lateral habitus; C. frontal habitus; D. male terminalia, left lateral view; E. male terminalia, caudal view.

FIGURE 18. Dorsal and lateral habitus of brachypters of select Chionomus species, A,D. Chionomus havanae, B,E. Chionomus balboae, C,F. Chionomus herkos, G,J. Chionomus pacificus, H,K. Chionomus puellus, I,L. Chionomus quadrispinosus.

FIGURE 30. Line art of Chionomus quadrispinosus terminalia, A. pygofer, caudal view, B. anal tube and aedeagus, left lateral view, C. left paramere, widest view.